The present invention relates to an improved construction of a motor-driven fuel pump for an internal combustion engine.
In my aforesaid parent application Ser. No. 802,532, there is proposed an improved fuel pump arrangement in which a motor unit has a cup-shaped motor housing and bearings so that it may be operated for a test before a pump unit is installed on a bottom portion of the motor housing. A pump rotor is carried by one end of a motor shaft extending from the bottom portion of the motor housing through key or spline arrangement. In the above construction, rust may gather on the surface of the key or spline arrangement of the motor shaft and the pump rotor.